Question

Some may already be noticing this and I would like to confirm it, I am really inexperienced with complex SQL strings. I only know simple SELECT , INSERT , UPDATE and DELETE statements. And to achieve my purpose I often use 2 SELECT statements, like this one :

con.Open();
string cmdstr = "SELECT UNIQUE FROM recipeList WHERE `stock_ID` = '" + stockIDTxtbox.Text + "'";
cmd = new MySqlCommand(cmdstr, con);
dr = cmd.ExecuteReader();
string menuID = "";
while (dr.Read())
{
   menuID = (dr["menu_ID"].ToString());
}
dr.Close();
con.Close();

con.Open();
string cmdstr = "SELECT `menu_name` FROM recipedb WHERE `menu_ID` = '" + menuID + "'";
cmd = new MySqlCommand(cmdstr, con);
dr = cmd.ExecuteReader();
string menuName = "";
while (dr.Read())
{
    menuName = (dr["menu_name"].ToString());
    this.listView1.Items.Add(new ListViewItem(new string[]{ menuName  }))
}
dr.Close();
con.Close();

Any ideas how to shorten this? o.O

Answer 1

You may write an SQL as:

 string queryString =  "SELECT r2.menu_name "+
                       "FROM recipelist rl "+ 
                          "INNER JOIN recipedb r2 "+
                          "ON rl.menu_ID = r2.menu_ID "+
                       "WHERE r1.stock_ID = '" + stockIDTxtbox.Text + "'";